Following up on r1466570, avoid doing unneeded work in a few common code paths.

* subversion/libsvn_client/cat.c
  (svn_client__get_normalized_stream): Use svn_wc__node_get_repos_info to
    obtain the url and the repository root.

* subversion/libsvn_subr/subst.c
  (keyword_printf): Just check against the empty string (=normalized form)
    instead of complete url check.

* subversion/libsvn_wc/translate.c
  (svn_wc__expand_keywords): Don't fetch the repository root url when just
    normalizing to the repository normal form.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1466596 13f79535-47bb-0310-9956-ffa450edef68